I mostly find that getting rewards is easy, because it's automatic every month. But discounts don't really matter because manual commissions are harder to think about in an ocean of options (and endless indecision stalemates). ._.

I prefer working knowing what the user wants rather than having to guess or come up with something, myself O: Considering I've been opening for sketches multiple times per month, as well, it gives more chances to be able to acquire them instead of having to wait the full month.
Getting sketch rewards innately every month only added stress once work piled up and left other stuff at a standstill (I used to have it like that). I figure having the slot system helped keep things in check. Tis just how I like working, personally!

Ye, I understand why it had to be this way, but my brain is too peanut to think about commissions (also I have anxiety about asking a lot of the time ;~;).